I doubt any amount of taxation would ever bring about revolution on the same scale as we had (which, by the way, was probably about 25-40% popularly supported). To reach that kind of dissent today would require some monumental stupidity on the part of the government - declaring the US a christian theocracy, suspension of the Bill of Rights, etc. Actions like those could easily motivate 10-25% of the population to arms. I can't believe it would ever happen though.
I think it's much more likely that we'll face collapse under the weight of our beauracracy combined with our spiraling debt and rambo-like foreign affairs policies. Or a continuing slow seperation into factions which bring about the breakup of the union to smaller unions or individual states. Of course, accompanying any such event would be limited violence, but hardly anything classifiable as an armed national revolution.